Actuators for the lift rods of circuit breaker contacts have in the past been relatively large mechanisms having slow time response. These large mechanisms have been necessary to overcome all the resisting forces that are encountered in a closing operation. Such forces result from the tail springs which are inside of the circuit breaker, the oil pumps, the friction of the tulip contacts and even the magnetic forces which occur when prestrike occurs. The large mechanism, such as depicted in U.S. Pat. No. 2,357,603, exemplifies the size and the space requirement that it has been necessary to provide for circuit breaker structures. In the past, in an effort to reduce the size of the toggle actuating mechanism and increase the efficiency of the actuators an overcenter five-bar toggle link arrangement has been provided in the circuit breakers. However, the five-bar arrangement is expensive and still requires more space than is practical or permissible and, of course, complicates circuit breaker design as well as increasing manufacturing costs. Thus, improvements which will materially reduce the size and complexities of component mechanisms that are required and at the same time increase the operating efficiency are an additional step forward.